Help for LAN connected device

Hello, I really need some help, I’m trying to write service manager and device handler for my TV, it is still an alpha stage, I can connect, turn on and off, but I don’t know how to update the TV’s attributes. I found this obscure chapter on the doc:
Is there any more documentation on this? Any working example I can study?

Other things, but less important:
I’d like to select the childDevice icon from the service manager, but can I find a way to choose/change the device icon from the service manager?
The same for the childDevice name, I can choose the name at creation, is there a way I can change the name if the device is already added?

Thank you for helping a newbie